1. Field of the Invention
The present invention generally relates to circuit breakers disposed in explosion proof enclosures and, more particularly, is concerned with an operating handle assembly mounted through a cover of the enclosure and being adapted to self-adjust its axial length so that the same handle assembly can used to reach and switch different circuit breakers of varying sizes when located in the enclosure at different distances from the enclosure cover.
2. Description of the Prior Art
Circuit breakers of differing physical configurations and varying sizes as well as electrical load capacities are commonly used in conjunction with electrical circuits and equipment. These circuit breakers typically can be switched between plural positions, such as "on", "off" and "reset". It is not uncommon for flashing of electrical arcs to occur with the switching of circuit breakers.
In certain industrial applications, the circuit breakers must be located inside of an enclosure which has an explosion proof characteristic so as to isolate the circuit breakers and any electrical arcs they might create from the surrounding environment. In these applications, handles are commonly provided which extend from the exterior of the explosion-proof enclosures into the enclosures to the circuit breakers. Users can then operate the circuit breaker by gripping and pivoting the handle to move an actuator lever in order to switch the enclosed circuit breaker between its various positions without opening the enclosure. However, due to the fact that circuit breakers by different manufacturers vary from one another in size, handles of different axial lengths have had to be provided to accommodate the different size circuit breakers. This increases overall equipment cost by requiring different handles to be designed and manufactured to accommodate the different circuit breakers.
Consequently, a need exists to design a handle which will accommodate different sizes of circuit breakers and thereby overcome the aforementioned problem.